1. Field of the Invention
The present invention relates to a motor vehicle wheel; and, more specifically, to a light metal wheel configuration.
2. Description of Related Art
Light metal wheels, cast from light metal alloys—for example aluminum or magnesium alloys, are known. They include a wheel rim that receives a tire and a plurality of wheel spokes connect the wheel rim to a wheel hub. The wheel hub fixes the wheel to the hub of the motor vehicle via wheel bolts. The light metal wheels are loaded during their use with increasing and decreasing dynamic bending and torsional forces. The cross-sections of the wheel spokes need to have dimensions in accordance with these loads. The achievement of a low weight, the compliance with desirable NVH properties (Noise, Vibration, Harshness), and an attractive appearance in such light metal wheels are significant factors.
A light metal wheel having a large number of wheel spokes is generally perceived to be more visually attractive than a wheel having a small number of wheel spokes. However, a large number of wheel spokes results, in comparison with a light metal wheel having the same weight and fewer wheel spokes, in a reduction of the inherent frequency of the light metal wheel and therefore to less favorable NVH properties. A light metal wheel having ten wheel spokes has an inherent frequency lower than a light metal wheel having only five wheel spokes for the same weight. A light metal wheel having a lower inherent frequency may produce undesirable loud noises perceived by the occupants of the motor vehicle. To achieve good NVH properties, the inherent frequency of a light metal wheel should be as high as possible. Furthermore, the cross-sections of the wheel spokes are usually relatively small in light metal wheels having a large number of wheel spokes, which results in an impairment of the wheel rigidity.